The present invention relates to apparatus for automatically connecting shutter slat and preventing its disengagement, and more particularly to apparatus which automatically connects one shutter slat with another having a notch and slots for preventing its disengagement, and which also prevents the connected shutter slats from being disengaged from each other without using conventional stop plate.
As is well known, shutter slats are connected by engaging the lower curved connecting edge of one shutter slat with the upper curved connecting edge of another shutter slat, but in this condition without any means to stop them, they are apt to get out of position or be disengaged.
Formerly, the only way to prevent this was to attach stop plates at the end of the connected shutter slats, but recently a new method of preventing disengagement of slats without using any stop plate has been developed.
According to this method, a notch is made in one part of the upper curved connecting edge of each shutter slat, and in a position of the lower curved connecting edge corresponding to that of said notch are provided a pair of slots, forming a tongue-shaped piece, which is bent after connecting the upper curved connecting edge of said each shutter slat with that of the lower curved connecting edge of each shutter slat adjacent thereto, so that the both sides of the tongue-shaped piece cross and contact the inside surface of the portion of the upper curved connecting edge having said notch.
The object of this invention is to provide an improved apparatus for automatically connecting efficiently shutter slats and preventing them from being disengaged in the above mentioned way.